RE: RPG400-L Digest, Vol 3, Issue 510 -- RPG400-L

There is a free progrm from Craig Rutledge < www.jcrcmds.com > that will
create D-Specs for stand-alone fields.  It puts them at the end of the
source and you have to move them to the proper place, but hey, it can't
all be free.  It also performs other tasks. I usually use this after I
have run the CVTRPGSRC. It's a great help and a good timesaver.

Good luck. I made the change 3 years ago.  I just coded in RPGIII and
learned the new opcodes as I went along.  ILE was a difficult concept at
first, but I got use to thinking in ILE. There is so much about this
version of the language that I couldn't do without now.  How quickly a
luxury becomes a necessity.

Marvin
[

date: Thu, 15 Jul 2004 11:49:08 +0000
from: Joel Cochran <jrc@xxxxxxxxxx>
subject: RE: Moving to RPGIV

On Thu, 2004-07-15 at 15:09, Dan Bale wrote:
> Pete, the first thing I did was to use CVTRPGSRC to convert RPG-III
apps I
> had written and was fairly familiar with.  The biggest hurdle for me
was the
> D-specs, and I've been known to code a snippet of I-specs in RPG-III
and
> convert that just to see the equivalent in RPG-IV.  But note that many
of
> the newer advanced features of D-specs are not utilized by the
converter
> (OVERLAY comes to mind).

If I remember right, CVTRPGSRC doesn't add D-Specs for stand alone
fields, so you'll have to do that by hand.  If you are used to Java and
C++, then the idea of defining all the variables at the top of the
source member won't be a big leap.  I agree it will probably take some
time to get familiar with some of the more advanced D-Spec techniques,
but you'll quickly find them superior to RPGIII.

> There isn't much that doesn't convert and these are typically some
arcane
> opcodes that no one uses anyway.

Doesn't everything from RPGIII convert to RPGIV?  I thought it was just
with /free and some expressions and such that things can't convert...

> The conversion also does not change "X   ADD   Y    Z" statements to
the
> "Eval   z = x + y".  And there are some rules regarding overflow that
cause
> these otherwise identical statements to behave differently that you
need to
> learn about.  Today, none of my programs use MOVEx, Z-ADD, ADD, SUB,
MULT,
> DIV, Z-SUB opcodes.

There are a couple of utilities out there for converting expressions.  I
think I got one with a book I bought, but it's been 4 years now so I
don't remember what book it was, but you could look for that when making
your purchasing decisions.

> Anyway, after you convert some programs, you'll see that there's
really no
> learning curve (especially since you're proficient in Java and C++),
and
> you'll see how the syntax between III and IV are different.
> 
> Moving ahead from just converting source, you'll find good information
on
> advanced -IV topics on this mailing list, and on several tech
newsletters
> (Club Tech comes to mind, there are others).  I keep the online IBM
RPG-IV
> Reference handy, as well as the "Who Knew You Could Do That With
RPG-IV?"
> redbook.  Bob Cozzi's book is, I think, considered the gold standard
for a
> commercial reference, but I have only browsed through others' copies.
You
> should remember to use the archives as well.

Moving to RPGIV is just the beginning of the journey... I don't think it
will take you too long.  For that, there are several books out there
that are specific to helping you make the transition.  The real leap
will come in moving from OPM to ILE.  For that, the "Who Knew..." and
the "ILE Concepts" Manual will prove indispensable.  And by all means do
yourself a favor and get a copy of Cozzi's "Modern RPGIV Language" as a
reference.  These are the books I reference the most.  "RPGIV At Work"
is also pretty decent.  And it goes without saying that this list and
others like it will prove invaluable to you... just check the archives
before you post...

As db said, "Welcome aboard!"

Joel
http://www.rpgnext.com